Apartment45 HOSTEL is just amazing. For the standing the prices are really cheap, the Hostel is new, everything is super clean, they provide a continental breakfast and there is one roof top with an incredible view of Bangkok.
The location is great because you have street food, Coffee Shop and a supermarket nearby, but also Metro, Skytrain and Lumphini Park if you like to find one good Park to run in the middle of BKK.
But the must of this place is the host, Kanin, a person super friendly everytime willing to help you and advice you about your stay in Bangkok or in Thailand.
He really wants you to spend a good time in Bkk, don't hesitate to Book here, you won't regret it!